Message type: E = Error
Message class:  ISU_GS_IN_SMS - Message class for IS-U: India localization for SMS Services 
Message number: 025
Message text: No valid mobile number maintained for the Customer &1.
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The SAP error message ISU_GS_IN_SMS025 indicates that there is no valid mobile number maintained for the customer in the system. This error typically occurs in the context of mobile communications or notifications, where the system attempts to send a message (like an SMS) to a customer but cannot find a valid mobile number associated with that customer.
Cause: Missing Mobile Number: The customer record does not have a mobile number entered. Incorrect Mobile Number Format: The mobile number may be present but is not in the correct format expected by the system. Customer Status: The customer may be inactive or not properly set up in the system, leading to the absence of a valid mobile number. Data Synchronization Issues: If the mobile number is maintained in another system or database, there may be synchronization issues preventing it from appearing in SAP.
Solution: Check Customer Master Data: Navigate to the customer master data in SAP (transaction code BP for
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